MMM-mode or more than one major mode, is a way of embedding various modes inside emacs!  Very cool!

#+BEGIN_SRC emacs-lisp
  (use-package mmm-mode
    :config
    (setq mmm-global-mode 'maybe)
    (mmm-add-classes
     '((embedded-elisp
        :submode emacs-lisp
        :face mmm-declaration-submode-face
        :front ".*#\\+BEGIN_SRC .*emacs-lisp.*"
        :back  ".*#\\+END_SRC.*")))
        (mmm-add-mode-ext-class 'org-mode ".*org.*" 'embedded-elisp))
#+END_SRC
